I wanted to play Star Wars Battlefront II, very slow FPS. So then I scraped that and I played DBZ Budokai Tenkaichi 3, couldn't play at full FPS either. Are my system requirements not meant for PS2 emulators? Or is it just misconfiguration of the settings on my part?

if using the mac port of pcsx2->your system doesn't meet pcsx2 requirements
if using the Wineskin port of pcsx2->probably a misconfiguration
if using the windows version on bootcamp->definitely a misconfiguration